Distributor vane operating apparatus for hydraulic turbines



May 22, 1956 Filed July 19, 1951 H. PEYRIN EI'AL DISTRIBUTOR VANEOPERATING APPARATUS FOR HYDRAULIC TURBINES 2 Sheets-Sheet l INVENTORSflew; Pegnw I Swarm java r l'asaza TTORA/E Y May 22, 1956 H. PEYRIN ETALDISTRIBUTOR VANE OPERATING APPARATUS FOR HYDRAULIC TURBINES 2Sheets-Sheet 2 Filed July 19 1951 INVENTOR. f/(nn aqrm 500!!! Jame! Q5 161 ,qrmmvEY United States Patent DISTRIBUTOR VANE OPERATING APPARATUSFOR HYDRAULIC TURBINES Henri Peyrin and Severin Xavier Casacci,Grenoble, France, assignors to Etablissements Neyrpic, Grenoble, France,a corporation of France Application July 19, 1951, Serial No. 237,633

Claims priority, application France August 4, 1950 3 Claims. (Cl.253-155) The present invention relates to distributor vane operatingapparatus for hydraulic turbines and particularly to servomotorapparatus and linkages connecting the servomotor apparatus to the vanes.

In order to direct the flow of water in a suitable manner through theturbine runner of a hydroelectric generating unit, a distributor iscommonly located upstream from the turbine runner. This distributor isusually formed of flow directing vanes disposed between two rigid framesfastened upon sills which are mounted on the masonry or concretefoundation. to vary the angle of attack of the water against the bladesof the turbine runner, there is commonly provided a first distributorhaving fixed blades and downstream therefrom a second distributor havingmovable blades. The simultaneous setting of these movable blades isusually accomplished by the rotation of a heavy disc called a shiftingring. The shifting ring rotates about the axis of the turbine andgenerator unit and is driven by means of one or more servomotors.

In turbine and generator units of the hydraulic type, the apparatus forpositioning the movable vanes of the distributor is commonly large andcomplex. In conventional turbine and generator units, there is usually aconsiderable space available between the turbine and the generator, andit is always possible to provide sufiicient space for the apparatus fordriving the shifting ring, however large and cumbersome that apparatusmay be. It is not practical to use such arrangements with turbine andgenerator assemblies of the unitary submerged type, such as disclosed inthe copending application of Jean Claude Guimbal, Serial No. 193,851,filed November 3, 1950, now Patent No. 2,634,375, issued April 7, 1953,,because of the necessity for giving to the assembly a streamlinedexterior form having suitable hydraulic characteristics.

It is very desirable in the latter case to locate all the mechanism forrotating the distributor vanes within the interior of the turbine andgenerator assembly so as to utilize to the maximum the space existingbetween the generator and the turbine. This space must be providedbecause of the dimensional requirement for obtaining optimum hydraulicflow conditions past the generator and through the turbine, which a viewto obtaining the best possible efficiency of the hydroelectric unit.This concentration of the apparatus within the unit is desirable notonly in unitary submerged assemblies, but also in turbine and generatorassemblies of other types.

An object of the present invention is to provide, in a turbine andgenerator assembly, an improved mechanism for operating the movablevanes of a distributor. A

further object is to provide such mechanism compactly located within theassembly so as to secure optimum hydraulic flow conditions.

This invention may be carried out in a turbine structure having adistributor section providing an outer casing and an inner casing aboutthe axis of rotation by When it is desired locating the apparatus whichpositions the shifting ring, particularly the servomotors, within theinterior of the inner distributor casing. The streamlined outer wall ofthe turbine and generator unit is provided with an enlarged diameterthrough the section where it is aligned with the distributor. Theprincipal active part within this section of the inner casing is themain shaft, which is much smaller than the inner casing, the latterbeing enlarged for streamlining purposes. In accordance with the presentinvention, the space within this section of the inner casing is utilizedas a location for the servomotors and the apparatus for positioning theshifting ring, so that there are no projections on the inner casingwhich would interfere with the smooth flow of water. There are likewiseno structures on the periphery of the annular frames on which thedistributor is mounted, nor is there any necessity for increasing thelength of the unit to receive this apparatus. In other words, the formand the length of the unit may be determined solely from therequirements for producing smooth hydraulic flow, without any necessityof compromise for the purpose of providing a space for the apparatuswhich positions the shifting ring.

This arrangement permits an inclination of the axes of the movable vaneswith respect to the axis of the turbine and generator unit, withoutincreasing the length of the unit. This inclination may be between 25and 55, which range is particularly favorable to a conical flow of waterthrough the turbine.

In one modification of the invention described herein, the servornotorsare or the conventional type, including pistons slidably mounted inright cylinders. The cylinders are directly pivoted on the inner casingof the distributor and the piston rods operated by the pistons arepivotally connected to lugs formed on the shifting ring.

In a modified form of the invention the servomotors consist of cylindersof toric form, with toric pistons moving therein. These pistons arefixed to the shifting ring by radial arms, and the toric cylinders arefixed to the frame of the distributor.

The invention will be more fully described with reference to the annexeddrawings, which show by way of example several embodiments of theinvention. In these embodiments, the apparatus for rotating thedistributor vanes is concentrated inside the inner casing upstream fromthe turbine, without external projections from the casings or from thelinings of the water passages.

Fig. l is a fragmentary view taken on a longitudinal section through aportion of a turbine and generator unit constructed in accordance withthe invention, with certain parts omitted for clarity.

Fig. 2 is an elevational view taken on the line 11-11 of Fig. 1, lookingin the direction of the arrows, with certain parts omitted.

Fig. 3 is a view similar to Fig. 1 showing a modification of theinvention.

Fig. 4 is a view similar to Fig. 2 showing still another modification ofthe invention.

Referring to Figs. 1 and 2, the tubine structure provides an outercasing comprising the crown rings 2 and 11 and the wall continuoustherewith and provides an inner casing comprising an internal crown ring3 and the member 7, these casings being circular in cross-section andconcentric upon the axis of the turbine shaft. A distributor for theturbine is shown, including fixed vanes 1, extending between theexternal crown ring 2, fixed to the outer wall of the water passage, andthe internal crown ring 3. The crown ring 3 is provided with an externalwall 4 and an internal wall 5. The crown ring 3 is attached at 6 to themember 7.

The distributor includes pivoted vanes 3 carrying on their inner endssupporting pins 9 which are journaled in the member 7. The pivoted vanes8 carry at their outer ends supporting pins 10 journaled in the crownring 11 fixed to the crown ring 2. The pivot pins 9 and 10 are axiallyaligned. The inner ends of the pivot pins 9 carry crank arms 12connected by pins 13 to links 14 which are connected at their oppositeends by means of pins 15 to an annulus 16 which serves as a shiftingring for the pivoted vanes 8.

The axes of the pivot pins 9, 13 and 15 intersect at a common pointlocated on the axis of the turbine and generator unit, so that nouniversal joint is needed in any of the pivot connections. In theparticular case of Fig. l, the axes of the pivot pins 15 on the shiftingring are radial, which greatly facilitates their manufacture. While thelinkage shown is preferred, other linkage arrangements, such as thoseincluding universal joints, may be employed.

The shifting ring 16 is provided with lugs 17, which may, for example,be four in number and symmetrically disposed. These lugs 17 form yokesfor receiving pivot pins 18 which pass through piston rods 19 operatedby pistons 20 which slide in right cylinders 21. The cylinders 21 andpistons 20 form fluid servomotors. The cylinders 21 are pivotallymounted at their ends opposite the piston rod 19. Preferably thispivotal mounting of the cylinders is carried out by means of pivot pins22 located in the space between the walls 4 and 5 of the crown ring.Suitable fluid couplings (not shown) may be provided, as is well-knownin the art, to supply fluid under pressure to the opposite ends of thecylinders 21 or to drain them, as required.

When it is desired to change the angle of the vanes 10, the controlvalve (not shown) of the servomotors operates to supply fluid throughthe coupling to one end of the servomotor and to connect the other to adrain, so as to establish a difference in the fluid pressure between thetwo faees of the pistons 20. The pistons are displaced within theircylinders 21 and rotate the shifting ring 16, which actuates the crankarms 13 through the links 14, thereby changing the angular position ofthe vanes 10.

During rotation of the shifting ring 16, the cylinders 21 pivot on theirpins 22.

In the modification shown in Fig. 3, the shifting ring 23 rotates on aninternal guide sleeve 24.

In the modification of Fig. 4, the operation of the shifting ring 23 isperformed by one or more servomotors in the form of toric cylinders 25fixed to the wall 26 of the crown ring 3 of the distributor.

Toric pistons 27 slide within the cylinders 25 and are connected byradial arms 28 to the shifting ring 23.

Whenever the servomotors are actuated to drive their pistons, theshifting ring turns through the same angle as the toric pistons.

This invention permits the location of the control apparatus for themovable vanes on a distributor within a minimum space, which permits theuse of a streamlined contour for the entire turbine and generatorassembly. Furthermore, the construction of the control apparatus issimple, strong and convenient, and eliminates many operating hazards.

It should be understood that the invention is not limited to theparticular modifications shown and described, but includes allvariations in those structures which are included within the terms ofthe appended claims.

We claim:

1. Flow distributing apparatus comprising an outer casing, an innercasing, said casings being of circular cross section and concentric anddefining between them an annular passage for flow of fluid therethrough,a flow controlling vane within said passage pivotally supported by saidcasings on an axis extending across said passage between said casings, ashifting ring disposed within said inner casing coaxial with andsupported to be rotatively movable upon the common axis of said casing,said ring eing disposed in inwardly spaced parallel relation to andadjacent said inner casing and having a radius upon said axis to providea substantial space within said ring about said axis, means operativelyconnecting said vane to said shifting ring for effecting pivotalmovement of said vane concurrently with said rotative movement of saidshifting ring upon said common axis to adjust the position of said vanein said fiow passage, a toric cylinder disposed within said inner casingand outwardly of said ring with respect to said common axis andsupported with the axis of the tore thereof concentric with said commonaxis, a toric piston movable to and fro within said toric cylinder inthe arc of the tore about said common axis, and an operative connectionbetween said toric piston and said ring for rotatively moving said ringforwardly and reversely upon said common axis upon to and fro movementof said toric piston to adjust the position of said vane in saidpassage.

2. Flow distributing apparatus as defined in claim l in which saidoperative connection between said toric piston and said shifting ringcomprises a rigid member rigidly supported by said ring and extendingoutwardly therefrom toward said toric piston, and an operativeconnection between said toric piston and said rigid member to effectmovement of said member and of said ring upon said movement of saidpiston.

3. Flow distributing apparatus comprising an outer casing, an innercasing, said casings being of circular cross section and concentric anddefining between them an annular passage for flow of fluid therethrough,a plurality of flow controlling vanes within said passage respectivelysupported on pivot shafts having their axes extending across saidpassage between said casings and supported by said casings, a shiftingring disposed within said inner casing coaxial with the common axis ofsaid casings and supported so as to be rotatively movable upon saidcommon axis, said ring being disposed in inwardly spaced parallelrelation to and adjacent said inner casing and having a radius upon saidaxis to provide a substantial space within said ring about said axis,means operatively connecting said pivot shafts to said shifting ring foreffecting pivotal movement of said shafts and the respective vanesconcurrently with said rotative movement of said shifting ring upon saidcommon axis to adjust the positions of said vanes in said flow passage,a toric cylinder disposed within said inner casing and between saidinner casing and said ring and supported by said inner casing with theaxis of the tore concentric with said common axis, a toric pistonmovable to and fro within said toric cylinder in the arc of the toreabout said common axis, and an operative connection between said toricpiston and said ring for rotatively moving said ring forwardly andreversely upon said common axis upon to and fro movement of said toricpiston to adjust the positions of said vanes in said passage.

References Cited in the file of this patent UNITED STATES PATENTS1,482,405 Moody Feb. 5, 1924 1,728,435 Moody Sept. 17, 1929 1,873,980Ring Aug. 30, 1932 1,892,187 Drennon Dec. 27, 1932 2,055,134 Pfau Sept.22, 1936 FOREIGN PATENTS 37,779 Norway Aug.-27, 1923 613,192 GreatBritain Nov. 23, 1948

